Fuel system for internal combustion engines



Aug. 27, 1935. F. J. HOLMES FUEL SYSTEM FOR INTERNAL COMBUSTION ENGINES Filed Dec. 11, 1933 amen V604 v E'ederck JEZWZGJ,

Patented Aug. 27, 1935 UNITED STATES PATENT OFFICE z-,o1z;2':s

Frederick J. Holmes, Detroit, Mleh., assignor, by mesne assignments, to Nnway Engineering garl'poration, Toledo, Ohio, a corporation of Application December 11, 1933, Serial No. 101,992

to burn more or less highly refined fuels, such by using gasoline as fuel it is desirable that I as gasoline, for operation by considerably heavier there shall be an unimpeded flow of fresh air fuels such as commercial fuel oil. to'the carburetor. Accordingly, another special The general object of the invention is to proobject of the invention is to provide means wherevide simple, reliable and efllcient means whereby, upon actuation of the fuel control valve to by ordinary so-called gasoline engines, such as place the gasoline supply pipe in communication 10 present day automobile, truck, boat and similar with the carburetor, anair supply control eleengines, may be made to operate economically ment is actuated to permita free flow of fresh 'and with increased power employing as fuel comair to the carburetor, and whereby, upon actuamercial fuel oil. tion of said fuel controlvalve to place the fuel Included in the fuel system of the ordinary oil supply pipe in communication with the carpresent day gasoline engine is a carburetor for buretor, said air supply control element is actuatomizing the gasoline prior to its introduction atedto assure a flow of heated air to the( carinto the intake manifold of the engine. In this buretor. connection a special object of the present inwith the foregoing and various other objects" vention is to provide a system whereby commerin view, which will become more fully apparent cial fuel oil maybe used'as fuel for ordinary as the natureof the invention is better undergasoline' engines and whereby the carburetors stood, the same consists in the novel combination ordinarily employed in conjunction with such enand arrangement of features as will be hereinafter gines may be utilized, without change, foratommore fully described, illustrated in the accomizing the fuel oil. a panying drawing and defined in the appended In order that an ordinary carburetor employed claims. in conjunction with an ordinary gasoline engine In the drawing, wherein is illustrated one pracmay be utilized for the atomization of commercial tical embodiment of the invention: fuel oil, it is necessary that the fuel oil be heated Figure 1 is a side elevation of an ordinary gasoprior to its introduction into the carburetor. line engine illustrating a fuel system in-accord- Accordingly,-anotherspecial object of the present ance with the invention applied thereto; and invention is to provide novel andhighly efficient Figure 2 is a detail view of the carburetor. means for utilizing the heat of the engine to Referring to the drawingindetaiLAdesignates, heat the fuel oil during its flow to .the carburetor. generally, an internal combustion engine which is Since, according to the present invention it is designed primarily for the use of gasoline as fuel necessary to heat the fuel oilprior to its atomand which includes, asusual, an intake 'maniization in an ordinary carburetor, and since, after fold l0, an exhaust manifold I I, and a carburetor more or less prolonged periods of idleness of I2 connected to the intake manifold. As shown, the engine-the. latter may become cold or inthe engine is of the water cooled type having a sufliciently warm properly to heat the fuel oil, water conduit l3 leading from its head for eon-' 40 I the invention contemplates an arrangement for nection with a radiator (not shown). using gasoline or similar light fuel for starting Connected to the float chamber M of the the engine and for using heavier oil as fuel after carburetor I2 is a valve l5, and connected to saidthe engine has been started and has become sufvalve are gasoline and fuel oil supplypipes I6 ficiently hot properly to heat the fuel oil. The and II, respectively, which are understood to lead by a single valve which is 5 Claims. (01. res- 121) tor for admixture with the atomized oil shall be This invention relates to fuel systems for in-' ternal combustion engines, and has particular reference to means to adapt internal combustion engines of the type which are primarily designed op rable to selectively deny communication bet ,een either of said pipes and the carburetor and to simultaneously place the other pipe in communication with the carburetor,-and a remote control handle or equivalent valve actuator is provided whereby the valve may readily be actuated by the operator of the engine. -When the engine is'operating on fuel oil it is desirable that the air admitted to the carburegasoline and fuel oil supply vjz'pes are controlled means for supplying heated air to the carburetor. when, however, the engine is to be started from any suitable sources of gasoline and fuel oil supply. The valve I5 is not illustrated in detail as it may be of any suitable or known type oper-' engine to actuate the valve to place either of the pipes l6 or il in communication with the carburetor, said handle in the present instance being rotatable through a suitable angle for this purpose.

When the engine is in operation the cooling water contained in the water jacket surrounding the engine cylinder or cylinders, of course, becomes heated, and in accordance with the invention the heated engine cooling water is utilized to heat the fuel oil prior to its introduction into the carburetor l2. To this end a small tank I9 is suitably mounted on or adjacent to the engine and at its bottom and top is connected, as at 20 and 2|, respectively, with the top portion of the water jacket of the engine and the conduit l 3. Thus, when the water within the water jacket of the engine becomes heated there results a constant circulation of hot water through the tank l9. Moreover, since the tank i9 is connected with the top portion of the water jacket of the engine where the water becomes most quickly heated and where the' hottest water tends to accumulate, only a minimum amount of time elapses after starting of the engine until the water circulating through the tank l9 becomes sufliciently hot properly to heat the fuel oil.

Now, in order that the hot water circulating through the tank i9 may be utilized to .heat the fuel oil, there is disposed within said tank a coil or coils through which the fuel oil flows in its travel from the tank or other source of supply to the carburetor. Preferably two coils 22 and 23 are employed arranged one within the other with their respective convolutions'spaced apart and with the convolutions of each alined with the spaces between the convolutions of the other, whereby an exceptionally rapid and eificient heat-. ing of the oil by the water is obtained. Preferably, too, the coils 22, 23 are formed as a unit separate from the oil supply pipe I1 and the two portions of said pipe are suitably detachably connected with the terminals of said coils. However, the coils may be formed directly in the pipe I1, and, of course, instead of the specific coil arrangement shown and described, any other suitable coil arrangement or heating means for the fuel oil may be provided. An arrangement utilizing the engine cooling water to heat the fuel oil is preferred, however, because of the substantially uniform heat which is derived from this source.

The carburetor 12 includes, as usual, an air supply conduit designated as 24, and in accordance with the invention there is connected with said conduit a hot air supply pipe 25 which leads from a stove or Jacket 26 which is suitably mounted in surrounding relationship to the engine exhaust pipe 21. The pipe 25 is connected to the conduit 24 through the instrumentality of .a T- iitting or the like 23 the outer end of which is equipped with ahinged closure 29. When this closure is opened atmospheric air may directly and unimpededly enter the air supply conduit 24 of the carburetor without being required to pass through the stove or Jacket 26 and the pipe 25. On the other hand. when the closure 29 is closed, all air entering the conduit 24 is required first to pass through the stove or jacket 26 and the pipe 25.

The closure 29 is intended to be opened to permit a free flow of atmospheric air to the carburetor when the engine is operating using gasoline as fuel, and to be closed to assure that heated air shall be supplied to the carburetor when the engine is operating using relatively heavy,

, present fuel system will be apparent.

oil as fuel, air passing through the stove or jacket 26 being heated by the hot exhaust pipe 21 as is, of course, understood.

The reason for opening the closure 29 to admit atmospheric air directly to the carburetor when the engine is operating using gasoline as fuel, and for closing said closure when the engine is operating using relatively heavy oil as fuel, is to render a single adjustment of the fuel control .valve of the carburetor suitable for operation of the engine on either gasoline or relatively heavy oil, and to avoid any necessity of changing said adjustment when changing from one fuel to the other. In this connection it has been found that by heating the air supplied to the carburetor when relatively heavy oil is used as fuel the required adjustment of the fuel control valve of the carburetor to obtain most efficient operation of the engine is substantially the same as the adjustment of said valve which is required to obtain most efficient operation of the engine when gasoline is used as fuel and at 'mospheric air is supplied directly to the carburetor, assuming, of course, that the fuel is in a heated state when it enters the carburetor as is the case according to the invention.

Now, in view of the foregoing, a feature of the invention resides in the provision of means whereby actuation of the handle i8 to cut off communication between the fuel oil supply pipe I! and the carburetor and to place the gasoline supply pipe IS in communication with them!- buretor, results in opening of the closure 29, and whereby, actuation of said handle to cut off communication between the gasoline supply pipe l6 and the carburetor and to place the fuel oil supply pipe H in communication with the carburetor, results in closing of the closure 29. The means mentioned may take avariety of forms depending upon the particular installation of the parts constituting the invention, but, as shown, a practical means for the purpose stated may comprise a lever arm 30 fixed to the handle I8 and connected to the closure 29 by a link or rod 3|. In addition, a spring 32 preferably is provided to maintain the closure 29 normally closed and to act through thelink 3|, the lever arm 30 and the handle l8 to maintain thevalve l5 normally adjusted to provide communication between the fuel oil supply pipe I! and the carburetor.

-It is desirable to provide means to heat the prevent flow of cooling air thereagainst, to avoid cooling of the fuel oil after it is supplied to the float chamber. Accordingly a trough like shield 33 is provided for this purpose, and, as shown, said shield preferably is mounted to extend between the exhaust manifold II and the float chamber l4 so as to direct hot air from the former to the latter.

In view of the foregoing the operation of the Assuming that the engine is cold, the handle I8 is actuated to place the gasoline supply pipe IS in communication with the carburetor and to open the closure 29. The engine then is started in the usual way and as long as the handle i3 is not disturbed the engine operates in the usual way using gasoline as fuel. However, because of the relative cheapness and greater power of fuel oil as fuel, it is desirable to switch over to the use of this fuel as soon as practicable after the engine has been started. Accordingly, following operation of the engine using gasoline as fuel and over a suitable period of time suflicient to heat the I water in the engine jacket and the tank l9, thus to heat the fuel oil, and by which time the exhaust manifold II and pipe 21 are hot, the handle I8 is actuated to operate the'valve I5 to cut oflf the supply of gasoline, to place the fuel oil supply pipe ll in communication with the carburetor and to close the closure 29. Heated fuel oil from the coils 22, 23 and heated air from the stove or jacket 26 then are supplied to the carburetor and the engine continues to operate at high efficiency usingthe fuel oil as fuel and without requiring any adjustment of the carburetor fuel control valve.

From the foregoing description considered in connection with the accompanying drawing, it is believed that the construction, operation and advantages oi. the invention will be clearly understood. It is pointed out, however, that while only a single specific structural embodiment of the invention has been illustrated and described, the same is readily susceptible of embodiment in specifically diiierent mechanical structures with in its spirit and scope as defined in the appended claims.

I claim:

1. In combination with an internal combustion engine including a carburetor, light and heavy fuel supply pipes connected to the carburetor, valve means operable to selectively place said pipes in communication with the carburetor, means for heating the heavy fuel prior to its delivery into the nozzle of the carburetor, an air heating device connected to the air intake conduit of the carburetor, means operable between two positions in one of which it requires air supplied to the carburetor to be first heated by said air heating device and in the other, of which it permits atmospheric air to be supplied directly to the carburetor without being heated by said heating device, and means whereby said last mentioned means is operated to its first and second mentioned positions in harmony with actuation of said valve to place the heavy and light fuel supply pipes in communication with the car buretor, respectively.

2. In combination with an internal combustion engine including a carburetor, light and heavy fuel supply pipes connected to the car- 1 buretor, valve means operable to selectively place said pipes in communication with the carburetor, an air heating device connected to the air intake conduit of the carburetor, a member operable between two positions in one of which it permits atmospheric air to directly enter the air intake conduit of the carburetor and in the other of which it requires air supplied to the carburetor to be first heated by said air heating device, and a connection between said valve means and said member whereby actuation of the valve means to place the light fuel supply pipe in communication with the carburetor actuates said member to its first mentioned position, and whereby actuation of said valve means to place the heavy fuel supply pipe in communication with the carburetor actuates said member to its second men tioned position;

3. In combination with an internal combustion engine including a carburetor, light and heavy fuel supply pipes connected to the carburetor, valve means operable to selectively place said carburetor without first being heated by said heating device and in the other of which it requires air supplied to the carburetor to be first heated by said heating device, a valve actuator, and a link and lever connection between said actutator and said member whereby actuation of said actuator to operate the valve means to place the light fuel supply pipe in communication with the carburetor moves said member to its firstmentioned position, and whereby actuation of said actuator to operate the valve means to place the heavy fuel supplypipein communication with the carburetor moves said member to its second mentioned position.

4. In combination. with an internal combustion engine including a carburetor, a water jacket and an exhaust conduit. light and heavy fuel supply pipes connected to the carburetor, a valve operable to selectively place said pipes in co cation with the carburetor, a handle for actuat ing said valve, means connected with the water jacket of the engine and utilizing the engine cooling water to heat the heavy fuel prior to its delivery to the carburetor, a jacket cooperating with the exhaust conduit to provide a source of heated airpa. connection between said last mentioned jacket and the carburetor, said connection having an opening for the admission of atmospheric air directly to the carburetor, a hinged member for controlling said opening, and a link and lever connection betweensaid valve actuating handle and said member whereby actuation of said handle to place the light fuel supply pipe in communication with the carburetor swings said member to an open position, and whereby actuation of said handle to place the heavy fuel supply pipe in communication with the carburetor results in closing of said member thereby to require air supplied to the carburetor to pass through said jacket.

5. In combination with an internal combustion engine including a carburetor, light and heavy fuel supply pipes connected to the carburetor, a valve operable to selectively place said pipes in communication with the carburetor, air heating means connected with the carburetor, said air heating means having an opening for the direct supply of atmospheric air to the carburetor. a member movable to an open position to permit a direct flow of atmospheric air to the carburetor and to a closed position to require air supplied to the carburetor to be first heated by said air heating means, a connection between said member and said valve whereby actuation of the latter to place the light fuel supply pipe in communication with the carburetor moves said member to an open position, and spring means tending constantly to move said member to a position closing said opening and acting through the connection between said member and said valve to intain the latter normally in a position placing the heavy fuel supply pipe in co cation with the carburetor. 

